Coast Guardsmen prepare to offload seized cocaine in San Diego in this October 2018 file photo. A leader in the Juarez drug cartel indicted in 1998 recently pleaded guilty to transporting cocaine and other narcotics to the U.S. and laundering the drug proceeds. (Associated Press)

A leader in a Mexican drug cartel pleaded guilty Thursday to transporting cocaine and other narcotics to the U.S. and laundering drug proceeds, the U.S. attorney’s office said.

Alvarez-Tostado obtained large quantities of cocaine from Colombia and transported it to various locations in the U.S. through Mexico, according to his plea agreement. Once distributed, he admitted to collecting and laundering the drug proceeds.

He was indicted in 1998 along with more than 100 other people and three major Mexican banks. He was arrested in Mexico in 2005 and charged with operating a continuing criminal enterprise, money laundering and conspiracy. He was extradited to the U.S. in 2018.

His capture was part of a Los Angeles-based investigation — Operation Casablanca — into drug money laundering by Mexican banks that was launched in 1995. Undercover officers from what was then the U.S. Customs Service set up shop in an L.A. warehouse and posed as freelance money launderers seeking assignments from Mexican drug dealers and bankers.

According to his plea agreement, Alvarez-Tostado supervised the collection and laundering of drug proceeds from distributors in the U.S. The money was transferred to his suppliers in Colombia, often through wire transfers to U.S. bank accounts he controlled.

A co-defendant, Victor Manuel Alcala-Navarro, directed undercover officers based in Santa Fe Springs to deliver money directly to them in Mexico and the U.S, according to the plea agreement. Alcala-Navarro and Alvarez-Tostado also directed the undercover officials to deliver proceeds to their cocaine suppliers in Colombia.

The drug proceeds were used to pay expenses of the drug trafficking enterprise and finance large shipments of drugs to the U.S.

Alvarez-Tostado’s sentencing is scheduled for March 28, according to the U.S. attorney’s office. Prosecutors are seeking a sentence of 18 years in prison, three years of supervised release and a fine set by the court.